The overarching purpose of this U19 Center grant application is to optimize a novel nanoparticle (NP) platform for the delivery of vaccines and vaccine adjuvants. The application is cross-disciplinary and requires expertise in material sciences, immunology, virology and animal models. We will test this platform for two viruses of high-medical need: influenza and Dengue virus. Once optimized, this platform should be adaptable for the delivery of vaccines against a variety of microbial pathogens. The NP technology platform is distinguished by the application of a soft lithography particle molding process called Particle Replication In Non-wetting Templates (PRINT) to produce the particles. This technology was developed by Dr. Joseph DeSimone at the University of North Carolina, who also founded the biotechnology company, Liquidia Technologies. A major advantage of PRINT is that the NPs produced are immunologically-inert and are of precise size, chemistry, porosity, flexibility and shape. Importantly, GMP (Good Manufacturing Practices) quality PRINT-NPs can be fabricated in large quantities by our industrial partner, Liquidia. A standard PRINT-NP has been used to deliver FDA-approved vaccines, with preliminary results demonstrating that this delivery system enhanced immunity compared to soluble vaccine and further provided a dose-sparing effect. This application has three projects based at UNC, supported by four cores that include industry-academia partnerships. All three projects are highly inter-related and have the ultimate goal of enabling an eventual IND application for optimized vaccine/adjuvant biologics. The first project will optimize the PRINT-NP chemistries to enhance biologic efficacy as a vaccine delivery system. The second project will focus on the co-delivery of PAMPs (Pathogen-associated Molecular Patterns) as adjuvants to stimulate anti-viral immunity in mice and appropriate larger animal models. The third project will use a novel humanized mouse system to assess human immune responses to NP-delivered vaccine and adjuvant. The three projects are highly integrated to discover the most optimal PRINT-NP platform needed for vaccine and adjuvant delivery for translation in humans.